Objective: To determine the accuracy of estimated fetal weight by ultrasound compared with actual birth weight. Study Design: Cross Sectional study. Setting: Department of Radiology, Fatima Memorial Hospital, Lahore. Period: September 2017 to January 2018. Material & Methods: A sample of 139 pregnant women who fulfilled the inclusion and exclusion criteria were included in this study Ultrasonography of full term pregnant women was performed to determine the comparison and accuracy with the actual weight of baby at birth. Results: In a sample of 139 pregnant women, the mean age was 27.8±4.2 years (with minimum age of 20 years and maximum age of 40 years). Ultrasonographic estimated fetal weight and actual birth weight was compared by using paired t-test. No significant difference was found between estimated fetal weight and actual birth weight with P-value 0.237. Conclusion: Ultrasound is highly sensitive, good, reliable, safe and accurate modality for estimation of fetal weight. There is no significant difference between fetal weight and actual birth weight.